Hi Yi,
On 1/17/23 14:49, Yi Liu wrote:
> This is preparation for adding vfio device cdev support. vfio device
> cdev requires:
> 1) a per device file memory to store the kvm pointer set by KVM. It will
> be propagated to vfio_device:kvm after the device cdev file is bound
> to an iommufd
> 2) a mechanism to block device access through device cdev fd before it
> is bound to an iommufd
>
> To address above requirements, this adds a per device file structure
> named vfio_device_file. For now, it's only a wrapper of struct vfio_device
> pointer. Other fields will be added to this per file structure in future
> commits.
>
> Signed-off-by: Yi Liu <yi.l.liu@xxxxxxxxx>
> ---
> drivers/vfio/group.c | 13 +++++++++++--
> drivers/vfio/vfio.h | 6 ++++++
> drivers/vfio/vfio_main.c | 31 ++++++++++++++++++++++++++-----
> 3 files changed, 43 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/vfio/group.c b/drivers/vfio/group.c
> index bb24b2f0271e..8fdb7e35b0a6 100644
> --- a/drivers/vfio/group.c
> +++ b/drivers/vfio/group.c
> @@ -186,19 +186,26 @@ void vfio_device_group_close(struct vfio_device *device)
>
> static struct file *vfio_device_open_file(struct vfio_device *device)
> {
> + struct vfio_device_file *df;
> struct file *filep;
> int ret;
>
> + df = vfio_allocate_device_file(device);
> + if (IS_ERR(df)) {
> + ret = PTR_ERR(df);
> + goto err_out;
> + }
> +
> ret = vfio_device_group_open(device);
> if (ret)
> - goto err_out;
> + goto err_free;
>
> /*
> * We can't use anon_inode_getfd() because we need to modify
> * the f_mode flags directly to allow more than just ioctls
> */
> filep = anon_inode_getfile("[vfio-device]", &vfio_device_fops,
> - device, O_RDWR);
> + df, O_RDWR);
> if (IS_ERR(filep)) {
> ret = PTR_ERR(filep);
> goto err_close_device;
> @@ -222,6 +229,8 @@ static struct file *vfio_device_open_file(struct vfio_device *device)
>
> err_close_device:
> vfio_device_group_close(device);
> +err_free:
> + kfree(df);
> err_out:
> return ERR_PTR(ret);
> }
> diff --git a/drivers/vfio/vfio.h b/drivers/vfio/vfio.h
> index f8219a438bfb..1091806bc89d 100644
> --- a/drivers/vfio/vfio.h
> +++ b/drivers/vfio/vfio.h
> @@ -16,12 +16,18 @@ struct iommu_group;
> struct vfio_device;
> struct vfio_container;
>
> +struct vfio_device_file {
> + struct vfio_device *device;
> +};
> +
> void vfio_device_put_registration(struct vfio_device *device);
> bool vfio_device_try_get_registration(struct vfio_device *device);
> int vfio_device_open(struct vfio_device *device,
> struct iommufd_ctx *iommufd, struct kvm *kvm);
> void vfio_device_close(struct vfio_device *device,
> struct iommufd_ctx *iommufd);
> +struct vfio_device_file *
> +vfio_allocate_device_file(struct vfio_device *device);
>
> extern const struct file_operations vfio_device_fops;
>
> diff --git a/drivers/vfio/vfio_main.c b/drivers/vfio/vfio_main.c
> index 5177bb061b17..ee54c9ae0af4 100644
> --- a/drivers/vfio/vfio_main.c
> +++ b/drivers/vfio/vfio_main.c
> @@ -344,6 +344,20 @@ static bool vfio_assert_device_open(struct vfio_device *device)
> return !WARN_ON_ONCE(!READ_ONCE(device->open_count));
> }
>
> +struct vfio_device_file *
> +vfio_allocate_device_file(struct vfio_device *device)
> +{
> + struct vfio_device_file *df;
> +
> + df = kzalloc(sizeof(*df), GFP_KERNEL_ACCOUNT);
> + if (!df)
> + return ERR_PTR(-ENOMEM);
> +
> + df->device = device;
> +
> + return df;
> +}
> +
> static int vfio_device_first_open(struct vfio_device *device,
> struct iommufd_ctx *iommufd, struct kvm *kvm)
> {
> @@ -461,12 +475,15 @@ static inline void vfio_device_pm_runtime_put(struct vfio_device *device)
> */
> static int vfio_device_fops_release(struct inode *inode, struct file *filep)
> {
> - struct vfio_device *device = filep->private_data;
> + struct vfio_device_file *df = filep->private_data;
> + struct vfio_device *device = df->device;
>
> vfio_device_group_close(device);
>
> vfio_device_put_registration(device);
>
> + kfree(df);
> +
> return 0;
> }
>
> @@ -1031,7 +1048,8 @@ static int vfio_ioctl_device_feature(struct vfio_device *device,
> static long vfio_device_fops_unl_ioctl(struct file *filep,
> unsigned int cmd, unsigned long arg)
> {
> - struct vfio_device *device = filep->private_data;
> + struct vfio_device_file *df = filep->private_data;
> + struct vfio_device *device = df->device;
> int ret;
>
> ret = vfio_device_pm_runtime_get(device);
> @@ -1058,7 +1076,8 @@ static long vfio_device_fops_unl_ioctl(struct file *filep,
> static ssize_t vfio_device_fops_read(struct file *filep, char __user *buf,
> size_t count, loff_t *ppos)
> {
> - struct vfio_device *device = filep->private_data;
> + struct vfio_device_file *df = filep->private_data;
> + struct vfio_device *device = df->device;
>
> if (unlikely(!device->ops->read))
> return -EINVAL;
> @@ -1070,7 +1089,8 @@ static ssize_t vfio_device_fops_write(struct file *filep,
> const char __user *buf,
> size_t count, loff_t *ppos)
> {
> - struct vfio_device *device = filep->private_data;
> + struct vfio_device_file *df = filep->private_data;
> + struct vfio_device *device = df->device;
>
> if (unlikely(!device->ops->write))
> return -EINVAL;
> @@ -1080,7 +1100,8 @@ static ssize_t vfio_device_fops_write(struct file *filep,
>
> static int vfio_device_fops_mmap(struct file *filep, struct vm_area_struct *vma)
> {
> - struct vfio_device *device = filep->private_data;
> + struct vfio_device_file *df = filep->private_data;
> + struct vfio_device *device = df->device;
>
> if (unlikely(!device->ops->mmap))
> return -EINVAL;
Reviewed-by: Eric Auger <eric.auger@xxxxxxxxxx>
Thanks
Eric
